1. Jyrki Laitinen: SPIE (1998), pp.34-45.
2. Z.W. Li: Machine Vision-based Online Printing Defect Detecting System Design (Master Thesis of Xi'an University of Architecture and Technology, China, 2008). pp.23-56.
3. X.Q. Peng: Research on Online Detecting Method for Product Surface Defect and System Implementation (Doctoral Dissertation of Huazhong University of Science and Technology, China, 2008).
4. Information on http: /www. vision-experts. de/en/print_expert_4000_content. html.
5. A M . Wallace: IEEE Proceedings, Part E: Computers and Digital Techniques, Vol. 135 (1988) No. 3, pp.117-136.